Reforming Capacitors With A Variac?

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jelle
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Joined: Sat Feb 04, 2006 7:55 pm
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Re: Reforming Capacitors With A Variac?

Post by jelle »

I am using these caps too, and have yet to see a problem with them. I have about 20 of those caps in the field. But, I use them in the preamp, not for power amp use.
The Ballzz
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Re: Reforming Capacitors With A Variac?

Post by The Ballzz »

CE/AES/Amplified Parts/Tubes & More is one the few companies I've encountered who actually seems to pay attention to their customers' concerns, comments & suggestions. I've pointed out listing/search issues on their website(s) and seen it corrected in a few days or even hours! I will always use them first, if it makes sense, as their customer service and prompt shipping has always been stellar! Not to mention, I always prefer to support smaller family style operations when possible! Their only downside is lack of coverage, but they improve almost daily.
Just My $.02,
Gene
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jelle
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Re: Reforming Capacitors With A Variac?

Post by jelle »

Yeah, CeDist/Tubesandmore is great. I love them.
gingertube
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Re: Reforming Capacitors With A Variac?

Post by gingertube »

Use R.G. 's method above.
I did my electronics training in the Biomedical Engineering Dept. of a major hospital. What R.G. suggests is EXACTLY what we used to do with Defibrillator Capacitors.
Well we actually built a dedicated bit of kit but monitoring the voltage drop across the large series resistor was how we determined when the cap was properly reformed. When the voltage across that resistor ceased dropping (usually after some HOURS) then the cap was reformed.

CAUTION to newbies: I hope the guys are talking about using a variac on the primary of a power tranny and then rectifying the secondary to apply to the cap. Thus creating a variable DC supply.
You don't want to apply AC to the cap (unless you want to destroy it).

PLUS: I'm always a little anxious when people say use a variac for anything, a variac is a variable auto-transformer, there is no isolation from input to output and so electrical safety is always compromised. Using a variac alone effectively doubles your electrical shock risk.

Cheers,
Ian
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